Electronic, magnetic and optical properties of Cu, Ag, Au-doped Si clusters

The structural, optical and magnetic properties of Cu, Ag, Au-doped Si-7 Clusters have been systematically investigated using density functional theory calculations. The global optimized structures of Cu, Ag, Au-doped Si clusters are predicted to have a lower HOMO-LUMO gap and higher magnetic moment. M-doping (M = Cu, Ag, Au) in Si cluster widens a range of adsorption wavelength, especially Au-doping. The characteristics in electronic density of states (DOSs) show that C-5v-Si6Cu has a big asymmetrical spin-up and spin-down. The average atomic moment is 0.428 m mu(B) per atom for the Si6Cu cluster with C-5v symmetry, while the average paramagnetic moment is 0.143 m mu(B) per atom for other M-doped (M = Cu, Ag, Au) Si-7 clusters.